Cadazolid is a new antibiotic developed for the treatment of Clostridiun difficile associated diarrhea (CDAD), also known as Clostridium Difficile Infection (CDI). The purpose of the study was to evaluate the efficacy and safety of different doses of cadazolid in order to find the dose of cadazolid to be used for further clinical development of the compound in subjects with CDAD.